Trisazo dyes



Patented May 31,1949 2,471,664

UNITED STATES ATENT OFFICE,

TRISAZO DYES Walter Wehrli. and Fritz Kehrer, Basel, Switzerland, assignors to Sandoz Ltd., Fribourg, Switzerland, a Swiss firm No Drawing. Application May 4, 1945, Serial No. 592,064. In Switzerland May 17, 1944 3 Claims. (01. 260173) The present invention relates to new trisazo tive, illustrates the present invention, the parts dyestuifs which dye cellulosic fibres in blue being by weight: shades, the fastness of which can be improved Example by an after-treatment with copper compounds, spans of t y1 5 t y I y and to process for them manufacture droxy-3'-carboXy-1:1-azobenzene are diazotized It has been found.that new vaiuable tnsazo in the usual way and coupled in presence of sodyestufis can be obtamed by couplmg 1 mole of dium carbonate, while cooling, with 4.6 parts of 5:5"d1hydm.Xy 2:2"dtnaphi3hy1amme 3 5:5'-dihydroxy-2:2'-dinaphthylamine-7:'1'-disulsulphonic acid, on one side, w1th 1 mole of a diazo phonic acid The disazo dyestuffs thus obtained compound prepared from an ammoazo dyestufi of is salted out, filtered, dissolved in water with adthe general formula dition of sodium carbonate and coupled in pres- HO ence of 10 per cent by volume of technical pyridine with the diazo compound prepared from 1.54

HOOO parts of 5-n1tro-2-am1no-l-hydroxybenzene.

if The trisazo dyestufi thus obtained is isolated A and dried; it dyes cotton and regenerated celluwherein losic fibres into brilliant reddish-blue shades that become greener, when after-treated with t d lk l, A S ands for by mgen or a y copper compounds, and the fastness to light and is: :3 g giggjg gf group and the wet fastness properties of which become strongly improved.

and, on the other slde, Wlth 1 mole of a dlazo The same dyestufi will be obtained, if first dicompound obtained from an o-aminophenol of the azotized 5 nitro 2 amino llhydroxybenzene and formula then the diazotized aminoazo dyestufl are coupled with the coupling component.

Dyestuffs of similar properties are obtained,

Q if instead of 3 parts of 4-amino-2-methyl-5-methoxy-4'hydroxy-3'-carboxy-1:1 azobenzene,

Z 3.2 parts of 4-amino-2:5-dimethoxy-4'-hydroxywherein Z stands for hydrogen, alkyl or halogen. b 1:1- b or 15 parts of 4- The trisazo dyestuffs obtainable according to amjno 2 5' djmethyl 5-methoxy-4' hydroxy-3'- the present invention dye cellulosic fibres, like cotcarboxyq lzazobenzene are d ton, linen and the like, and fibres from regenersimilar dyestuffs 111 l be t i if ated cellulose in clear blue shades, the fastness stead of 154 parts of 5 ii; gi -1- d Of which a e proved by a after-treatment benzene, there are used 1.88 parts of 5-nitro-4- wi h copp ri a wh y especially the chloro-Z-amino-l-hydroxybenzene or 1.68 parts fastness to light and the wet fastness properties of 5 nitro-4-methyl-2-amino-l-hydroxybenzene,

are improved. The new dyestuffs possess an ex- Wh t we l im is; cellent afiinity for cellulosic fibres. 40 1. The dyestuffs of the general formula on, noas- NH -so,H OH HO I N=N 'N=N= -N=N N0:

A $011, H H z The coupling of the 5:5'-dihydroxy-2:2diwherein Z stands for a member selected from naphthylamine-7: 7'-disulphonic acid can be carthe group Consisting of y e a y a d ha oried out in the usual way in presence of alkaline fig 3 1 5? 2 35 23223 zg g gigy g ggg compounds sodmm b%carbonate Sodmm car dyestuffs dye cellulosic fibres in blue shades,

bonate, ammoma or Pyndmewhich, when after-coppered, become improved in The following example, Without being limitatheir fastnesses to light and wet treatments,

2. The dyestufl of the formula which dyestufi dyes ce11u1 osic fibres in blue shades,

HO 0H, Ho's NH 30.11 H0 1100 c N=N N=N N=N N0:

OCH; H H

which dyestuff dyes eellulosic fibres in blue shades, h when P become improved which when aftepcoppered become improved in than fastnesses to hght and wet treatments.

in their fastnesses to light and wet treatments. WALTER WEHRLI- 3. The dyestufli of the formula. FRITZ KEI-IRER.

110-- (RH; H0 s- NH SO3H n! HOOC N=N -N=N N=N-C N0z (50H; (BB1 H ()1 REFERENCES CITED The following references are of record in the file of this patent:

I UNITED STATES PATENTS FOREIGNYPA'IYENTS Number Name Date Number Country Date 1,265,031 Anderwert May '7, 1918 497,350 Great Britain Dec. 19, 1938 2,092,429 Straub et a1 Sept. 7,. 1937 2,369,516 Anderan Feb. 13, 1945 

